I agree with Bounceback. You really should go to the hospital or Mental Health Clinic near you and explain to them your fears and what you're experiencing. It must be very frightening to you to feel you're being attacked with knives and abused. but I will go out on a limb here to say that what you're describing to us is a serious illness that needs attention and help from real professions.
Also, do you have any relatives or friends who can help you go to a hospital?
If not, it would be a good idea to call 911 and ask for help. If you're really being attacked, they are the ones to come and rescue you, and if you are hallucinating something so convincing, it is still right to call 911 so you can get safely to a hospital where there will be help for your ongoing nightmare situation.